Add check for support for Read-Wrie images

Read-Write images have required OpenCL 2.x.
Read-Write image tests are already being skipped
for 1.x devices.
With OpenCL 3.0, read-write images being optional,
the tests should be run or skipped
depending on the implementation support.

Add a check to decide if Read-Write images are
supported or required to be supported depending
on OpenCL version and decide if the tests should
be run on skipped.

Fixes issue #894

test_conformance/images/samplerlessReads/test_read_1D.cpp

@@ -196,6 +196,11 @@ int test_read_image_set_1D( cl_device_id device, cl_context context, cl_command_
     RandomSeed seed( gRandomSeed );
     int error;
 
+    if(gTestReadWrite && checkForReadWriteImageSupport(device)) 
+    {
+        return TEST_SKIPPED_ITSELF; 
+    }
+
     // Get our operating params
     size_t maxWidth;
     cl_ulong maxAllocSize, memSize;